Purified component of blue-green algae and method of use

ABSTRACT

Disclosed herein are extracts of blue green algae, such as  Aphanizomenon flos aquae , that are enriched for a selectin ligand, such as an L-selectin ligand. Selectin ligands isolated from blue-green algae cells are disclosed herein. Methods are described for isolating these selectin ligands. The purified selectin ligands are of use in inducing stem cell mobilization in a subject. Thus, methods for inducing stem cell isolation that include administering a therapeutically effective amount of the extract enriched form the selectin ligand, or an isolated selectin ligand, are disclosed herein.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/693,808, filed Jun. 24, 2005, and U.S. Provisional Application No.60/700,882, filed Jul. 19, 2005. Both of the provisional applicationsare incorporated by reference herein in their entirety.

FIELD

This application relates to an aqueous extract from blue-green algae,such as an aqueous extract of algae that includes a selectin ligand.

BACKGROUND

Stem cells are pluripotent cells derived from somatic tissue capable ofdifferentiating into more specialized cells. For example, hematopoieticstem cells can differentiate into many different types of blood cells,including red blood cells, platelets, and leukocytes.

Hematopoietic stem cells play a role in the continuous lifelongphysiological replenishment of blood cells. Stem cells develop into bothhematopoietic lineage cells and non-hematopoietic, tissue specificcells. Recently, stem cells have been found to differentiate into avariety of tissue-specific cell types, such as myocytes, hepatocytes,osteocytes, glial cells, and neurons. For example, stem cells have beenshown to cross the blood-brain barrier (Willams and Hickey, Curr. Top.Microbiol. Immunol. 202:221-245, 1995) and differentiate into neurons(Mezey, Science 290:1779-82, 2000). Thus, it is possible that stem cellscould be used to treat Parkinson's disease (Polli, Haematologica85:1009-10, 2000), Alzheimer's disease (Mattson, Exp. Gerontol.35:489-502, 2000), and traumatic brain injury (Magavi, Nature 405:892-3, 895, 2000). Stem cells also have been shown to differentiate intofibroblasts or fibroblast-like cells, and to express collagen (Perieraet al., Proc. Natl. Acad. Sci. 95:1142-7, 1998). Thus, it is possiblethat stem cells can be used to treat osteogenesis imperfecta and bonefractures. Peterson et al. (Science 284:1168-70, 1999) also has shownthat liver cells can arise from stem cells. Thus, stem cells may be ofuse in treating a variety of pathologies of the liver, including, butnot limited to cirrhosis. In addition, bone marrow derived stem cellshave been demonstrated to migrate to the site of a myocardial infarctionand form myocardium (Orlic, Nature 410:701-5, 2000). Thus, stem cellsmay be use in treating myocardial infarction.

Since stem cells are capable of differentiating into a broad variety ofcell types, they play an important role in the healing and regenerativeprocesses of various tissues and organs (see Koc et al., Bone MarrowTransplant, 27(3):235-39, 2001). Selectin ligands stimulate the releaseof stem cells from the bone marrow (Frenette et al., Blood 96:2460-68,2000).

Many studies suggest that the mobilization, migration anddifferentiation of bone marrow stem cells in the target tissueconstitute a natural phenomenon of healing in the human body (Spencer etal., Thorax 60(1):60-2, 2005; Ishikawa et al., FASEB J. 18(15):1958-60,2004; Mattsson et al., Transplantation 15;78(1):154-7, 2004; Thiele Jetal., Transplantation 77(12):1902-5, 2004; Cogle et al., The Lancet363(9419):1432-7, 2004; Deb et al., Circulation 107(9):1247-9, 2003;Korbling et al., N Engl J Med 346(10):738-46, 2002; Adams et al., Blood102(10):3845-7, 2002; Krause et al., Cell 105(3):369-77, 2001).Mobilized stem cells follow concentration gradients of cytokinesreleased by damaged tissues and migrate on their own into tissuesfollowing such gradients. Indeed, the mobilization of bone marrow stemcells induced by cytokines injection has been shown to accelerate thehealing the cardiac tissue after acute myocardial infarction. Therefore,simply triggering the mobilization of bone marrow stem cells with aneffective and safe consumable can enhance this natural physiologicalprocess and provide a potential therapy for various pathologies. Thus,there is a need for compositions that increase stem cell mobilizationand trafficking.

SUMMARY

An exemplary procedure is disclosed for obtaining an aqueous extract ofblue-green algae containing a selectin ligand. In this procedure, aselectin ligand is isolated from blue-green algae using a solidsubstrate covalently bound to a selectin, such as L-selectin,P-selectin, and/or E-selectin. The selectin ligand can specifically bindL-selectin, P-selecting and/or E-selectin.

Purified selectin ligands that are isolated from blue-green algae aredescribed. These ligands are isolated from blue-green algae that are aprotein or a glycoprotein of a molecular weight of about 55 kDa underreducing conditions. In several examples, the selectin ligand has amolecular weight of about 54 kDa or about 57 kDa under reducingconditions. In additional examples, selectin ligand has a molecularweight of about 54 kDa, about 57 kDa, about 162 kDa, about 171 kDa,about 233 kDa or about 111 kDa under non-reducing conditions.

An extract of Aphanizomenon flos aquae (AFA) is disclosed herein thatcontains L-selectin ligand. This extract can be formulated foradministration to a subject. Compositions including the extract alone,or including other extracts of Aphanizomenon flos aquae (AFA) can beadministered to a subject in need of stem cell mobilization and/orincreased number of circulating stem cells. In one example, the extractcontainng the L-selectin ligand is administered with an extract ofAphanizomenon flos aquae (AFA) containing polysaccharides. Compositions,which include or consist of the L-selectin ligand of Aphanizomenon flosaquae (AFA) are of use for stem cell mobilization and increasing thenumber of circulating stem cells.

A method is disclosed herein for triggering stem cell mobilization byadministering a therapeutically effective amount of a specific extractof blue-green algae to a subject. Extracts of use in inducing stem cellmobilization include extracts of blue-green algae containing a selectinligand, such as an L-selectin, P-selectin and/or an E-selectin ligand.In one example, the blue-green algae is Aphanizomenon flos aquae (AFA).The extracts can be administered alone or in conjunction with otherextracts of Aphanizomenon flos aquae (AFA). In one example, apolysaccharide containing extract is also administered.

The administration of a therapeutically effective amount of an extractof the blue-green algae, such as a selectin ligand containing extract,induces a transient increase in the population of some stem cells, suchas CD34+ stem cells and/or CD133+ stem cells, in the subject'scirculatory system.

The foregoing and other features and advantages will become moreapparent from the following detailed description of several embodiments,which proceeds with reference to the accompanying figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is line graph showing a time course for increase in the number ofcirculating stem cells in the blood of healthy humans upon ingestion ofAFA. Flow cytometry was performed on human lymphocytes and monocytes,where the monoclonal antibody CD34, with specificity for human stemcells was used to demonstrate that AFA extract A contains a compoundthat mobilizes stem cells by increasing their numbers in the bloodcirculation.

FIG. 2 is a bar graph showing flow cytometry that was performed on humanlymphocytes, monoclytes, and polymorph nucleated cells, where themonoclonal antibody TQ1, specific for the ligand-binding area of humanL-selectin, was used to demonstrate that AFA extract A contains acompound that competes for binding on the L-selectin ligand-bindingsite. The effect of competition between the TQ1 antibody and thecompound from AFA Extract A is concentration-dependent.

FIG. 3 is a schematic illustration of the method used to purify theselectin ligand from AFA Extract A. Magnetic beads were coated withProtein G, which binds the Fc portion of immunoglobulin. These beadswere used to capture a chimerical recombinant protein consisting of theextracellular portion of human L-selectin, joined together with the Fcportion of human immunoglobulin IgG1. A chemical reaction was performedto form covalent bindings between the Fc portion of the chimera and theProtein G on the magnetic beads. These beads, now coated with thechimera, with the extracellular portion of human L-selectin reaching outfrom the beads, were used to capture the ligand for L-selectin in AFAextracts.

FIGS. 4A-4B are digital images that show gel electrophoresis thatillustrates the approximate molecular weight of the compound that wasaffinity purified from AFA extract A, when the affinity method describedin FIG. 3 was employed. The figures are digital images of gels, whereingel electrophoresis was performed on material eluted off the magneticbeads after these beads had captured the selectin ligand from AFAExtract A. FIG. 4A is a digital image that shows the compound elutedfrom beads that were coated with human recombinant L-selectin, and FIG.4B is a digital image that shows the compound eluted from beads coatedwith human recombinant P-selectin. The gels were run under reducingconditions. Two distinct bands at approximately 54 and 57 kDa are shown.Identical band patterns were seen for both L- and P-selectin, indicatingthat the selectin ligand is a ligand for both L- and P-selectin.

FIG. 5 is a digital image of a gel, wherein gel electrophoresis wasperformed on material eluted off the magnetic beads after these beadshad been utilized to capture potential selectin ligands in AFA Extract Aversus Extract B. The selectin ligand from AFA was found in Extract A.No selectin ligand from AFA can be detected in Extract B. Lane 1 is anegative control, Lane 2 shows the ligand purified from Extract A(arrow), and Lane 3 shows that a corresponding band was not seen inExtract B.

FIG. 6 is a line graph showing the results from flow cytometry analysisof the expression of the chemokine receptor CXCR4, as it is induced by aknown L-selectin ligand, Fucoidan. The data indicates that the knownL-selectin ligand Fucoidan, competes with the compound from AFA forbinding to L-selectin on human peripheral blood lymphocytes.

FIG. 7 is a line graph showing the results from a flow cytometryanalysis of the expression of the chemokine receptor CXCR4, as it isinduced by a known L-selectin ligand, Fucoidan. The data indicates thatthe known L-selectin ligand Fucoidan, competes with the compound fromAFA for binding to L-selectin on the human CD34+ cell line KG-1a.

FIG. 8 is a Table. The results presented show that Extract A (AFA-W)blocks binding of TQ1 MoAb to L-selectin on human leukocytes.

FIG. 9 is a line graph showing the time course of the number of CD34+cells in human peripheral blood after consumption (arrow) of L-selectinligand (LSL), migratose (MGT), stem enhanced combination (SE) or aplacebo (labeled Ctrl). L-selectin ligand (LSL) is an extract ofAphanizomenon flos aquae (AFA) enriched for the L-selectin ligand. Forthe subjects treated with LSL, one gram of the extract concentrated inL-selectin ligand (see the examples section) was mixed in 40 ml of waterand consumed by the subject. Migratose (MGT) is an extract whereinliquid Aphanizomenon flos aquae (AFA) was extreacted with 10% ethanol at85° C. for three hours. The solution was centrifuged and the supernatantwas dried using RW. For administration, 150 mg of the dried product wasblended with 250 mg of a carrier, encapsulated in a vegetable capsuleand consumed by the subjects. Stem enhance combination (SE) was a blendof LSL and MGT, as described above. One gram of SE was mixed in 40 ml ofwater and consumed by the subjects. The control was 400 mg of finelyground potato flakes encapsulated in vegetable capsules.

DETAILED DESCRIPTION

I. Abbreviations

AFA: Aphanizomenon flos aquae

Ctrl: control

LSL: L-selectin ligand

mg: milligram

ml: milliliter

MGT: migratose

SE: stem enhance combination, includes LSL and MGT

g: gram

kg: kilogram

II. Terms

Unless otherwise noted, technical terms are used according toconventional usage. Definitions of common terms in molecular biology maybe found in Benjamin Lewin, Genes V, published by Oxford UniversityPress, 1994 (ISBN 0-19-854287-9); Kendrew et al. (eds.), TheEncyclopedia of Molecular Biology, published by Blackwell Science Ltd.,1994 (ISBN 0-632-02182-9); and Robert A. Meyers (ed.), Molecular Biologyand Biotechnology: a Comprehensive Desk Reference, published by VCHPublishers, Inc., 1995 (ISBN 1-56081-569-8).

In order to facilitate review of the various embodiments of thisdisclosure, the following explanations of specific terms are provided:

Administration to a subject. Providing blue-green algae to a subjectincludes administering whole blue-green algae cells and/or extracts(fractions) of blue-green algae cells. Routes of administration include,but are not limited to, oral and parenteral routes, such as intravenous(IV), intraperitoneal (IP), rectal, topical, ophthalmic, nasal, andtransdermal. Oral administration includes both whole blue-green algaeand extracts of blue-green algae. More than one extract can beadministered. If administered orally, the whole cells or extracts may beprovided or administered in the form of a unit dose in solid,semi-solid, or liquid dosage form such as tablets, pills, powders,liquid solutions, or liquid suspensions. However, extracts of blue-greenalgae also may be administered intravenously in any conventional mediumfor intravenous injection, such as an aqueous saline medium, or in ablood plasma medium. The medium also may contain conventionalpharmaceutical adjunct materials, such as pharmaceutically acceptablesalts to adjust the osmotic pressure, lipid carriers (e.g.,cyclodextrins), proteins (e.g., serum albumin), hydrophilic agents(e.g., methyl cellulose), detergents, buffers, preservatives, and thelike. A more complete explanation of acceptable pharmaceutical carrierscan be found in Remington: The Science and Practice of Pharmacy (19^(th)Edition, 1995) in chapter 95.

Agent that affects hematopoiesis. A compound, antibody, nucleic acidmolecule, protein, glycoprotein, or cell that alters the formation ofblood cells, such as white blood cells. A molecular agent can be anaturally occurring molecule or a synthetic molecule. In someembodiments, the agent affects the mobilization, growth, proliferation,maturation, or differentiation or release of hematopoietic cells. In oneembodiment, the agent is a selectin ligand extracted from a blue-greenalgae cell.

Agent that affects stem cell circulation. A compound, antibody, nucleicacid molecule, protein, glycoprotein, or cell, including neuropeptidesand other signaling molecules, that affects the release of stem cellsinto the circulatory system, as well as homing from the circulatorysystem into tissue. A molecular agent may be a naturally occurringmolecule or a synthetic molecule. In one specific example, the agent isa selectin ligand from blue-green algae.

An agent that affects stem cell circulation may affect the ratio of stemcells in the quiescent pool versus the active pool. In some embodiments,the agent affects the balance between undifferentiated stem cells andstem cells differentiating into CD34− negative (CD34−) and CD34-positive(CD34+) cell, and/or CD133-negative (CD133−) and CD133-postive (CD133+)cells. In other embodiments, the agent affects the release of stem cellsfrom tissue locations, such as the release of CD34+ cells and/or CD133+cells and/or cells detected by methods based on the enzymatic actions ofaldehyde dehydrogenase, from the bone marrow environment.

Animal. A living, multicellular, vertebrate organism including, forexample, mammals, fish, reptiles, and birds.

Blue-green algae. Common name for gram-negative photosynthetic bacteriabelonging to Division Cyanophyta that may exist in unicellular,colonial, or filamentous forms. Representative blue-green algae include,but are not limited to, Spirulina species and Aphanizomenon species.Aphanizomenon flos aquae (AFA) is one specific, non-limiting type ofblue-green algae.

The term “algae” is the plural form of “alga,” which is a cell of amicroalgae species. For example (and without limitation), “blue-greenalgae” refers to multiple cells of a single Aphanizomenon species,multiple cells of a single Spirulina species, or a mixture of cells frommultiple Aphanizomenon and/or Spirulina species.

Circulatory system. In animals, the circulatory system is composed ofthe structures that move blood and blood components throughout the body,including the vascular and lymph systems. The components of thecirculatory system include the heart, blood vessels (arteries, veins,and capillaries), and lymph vessels.

Circulating stem cell. A stem cell present in the circulatory system.

Component of blue-green algae. Any fraction, extract, or isolated orpurified molecule from a blue-green algae cell. In one embodiment, thecomponent is a protein or a glycoprotein or nucleic acid. In anotherembodiment, the component is a component is a phytochemical. In anotherembodiment, the component is an aqueous extract of a blue-green algaeincluding a selectin ligand. Thus, the blue-green algae is disrupted, aninorganic or organic solvent is added, and extracts are collected.Specific, non-limiting examples are extracts isolated using highperformance liquid chromatography, thin layer chromatography, affinitycolumn, magnetic beads or distillation. In one embodiment, fractionationis based on the molecular weight or the hydrophobicity of the componentsof the blue-green algae.

Differentiation. The process by which cells become more specialized toperform biological functions. Differentiation is a property that isoften totally or partially lost by cells that have undergone malignanttransformation.

Effective amount. An amount, such as an amount of a selectin-containingextract of blue-green alga, capable of triggering or enhancing stem cellmobilization, which can be determined by various methods used in thebiological sciences. These methods include, but are not limited to,generating an empirical dose-response curve.

In one embodiment, a “therapeutically effective amount” is an amounteffective for enhancing mobilization of stem cells that replenish,repair, or rejuvenate tissue. In another embodiment, a “therapeuticallyeffective amount” is an amount effective for enhancing trafficking ofstem cells. In still another embodiment, the “therapeutically effectiveamount” is an amount effective for enhancing homing of stem cells fromthe circulatory system to various tissues or organs.

A therapeutically effective amount also may be an amount sufficient fortreating a condition or disease, such as an amount sufficient to relievesymptoms associated with nervous system disorders (for example,Alzheimer's disease, Parkinson's disease, multiple sclerosis), traumaticbrain or spinal cord injury, liver disease, or disorders of bone orcartilage. A therapeutically effective amount may also be an amountsufficient for accelerating and enhancing the recovery from acutemyocardial infarction.

In one specific, non-limiting example, the therapeutically effectiveamount of the extract, such as a selectin-containing extract ofblue-green algae, is from about 0.01 to about 1.0 g per kg body weight,such as about 0.05 to about 0.5 gram per kg body weight, or from about0.1 to about 0.5 gram per kg body weight. In another specific,non-limiting, example the effective amount of the selectin-containingextract of blue-green algae is from about 0.25 gram to about 5 gram, offrom about 0.5 gram to about 5 gram, or from about 1 gram to about 2gram. In one specific, non-limiting example, the effective amount ofselectin-containing extract of blue-green algae is 1 gram. Thiseffective amount may be administered at a given frequency, such as aboutonce a week, about twice a week, about three times a week, once a day,about twice a day, about three times a day, or more.

The therapeutically effective amount of an extract of blue-green algae,such as a selectin-containing aqueous extract of blue-green algae andfrequency of administration may depend on a variety of factors, such asthe genus or species of algae utilized, the general health of thesubject being treated, and the physiological characteristics (e.g.,height, weight, body fat percentage, metabolism, etc.) of the subjectbeing treated.

Specific assays for determining a therapeutically effective amount of anaqueous extract, such as a selectin ligand-containing extract, ofblue-green algae are provided herein. In one specific, non-limitingexample, different amounts of a selectin ligand-containing extract ofblue-green algae, such as AFA, are consumed by human subjects and thepresence and/or quantity of stem cells (which can include subtypes ofsuch cells) present in the circulatory system is detected and/oranalyzed. In another embodiment, an animal (e.g. murine) model isutilized, and the population of newly integrated stem cells is monitoredin various tissues (see the Examples below). The methods disclosed haveequal application in medical and veterinary settings. Therefore, thegeneral term “subject being treated” includes all vertebrates (forexample, but not limited to, humans, apes, dogs, cats, mice, rats,rabbits, sheep, horses, pigs, and cows).

Enhancement (enhancing). An increase in a particular parameter of a cellor organism. In one embodiment, enhancement refers to a 25%, 50%, 100%or greater than 100% increase in a parameter. In one specific,non-limiting example, enhancement of stem cell circulation refers to anincrease in a specific population of the cells, such as a 25%, 50%,100%, 200%, 400%, 500%, or greater increase in the specific populationof cells or the response of the population of cells. In one embodiment,the parameter is the mobilization of stem cells. In another embodiment,the parameter is the differentiation of stem cells. In yet anotherembodiment, the parameter is the homing of stem cells.

Erythrocytes. Red blood cells that carry oxygen to tissues of the body.

Extract. A concentrated preparation of a composition, such as ablue-green algae, obtained by removing the active constituents of thecomposition with suitable solvents, evaporating all or nearly all of thesolvent, and adjusting the residual mass or powder to the apre-determined standard amount. An extract is “enriched” for a product,such as a selectin ligand, if the activity or amount of a component ofinterest is increased substantially in the extract as compared to otherextracts or to the same amount of the extracted original composition.

Glycoprotein. A complex molecule made of a protein moiety and a glycanor polysaccharide moiety.

Hematopoiesis. The formation and development of blood cells.Hematopoiesis involves the proliferation and terminal differentiation ofhematopeoietic stem cells. In adult mammals, hematopoiesis is known tooccur in bone marrow. Hematopoiesis is the production of hematopoieticcells including B cells, T cells, cells of the monocyte macrophagelineage, and red blood cells.

Homing. The process of a cell migrating from the circulatory system intoa tissue or organ. In some instances, homing is accomplished viatissue-specific adhesion molecules and adhesion processes.

Immunologically normal. “Immunologically normal” denotes a subject thatdisplays immune system characteristics typical for the species to whichthe individual belongs. These typical characteristics include, amongothers, functioning B cells and T cells as well as structural cellcomponents, called cell surface antigens, which act as the immunologicsignature for a particular organism.

The use of such immunologically normal recipients means that animmunologically normal recipient's immune system, via its B (humoralresponse) and T (cellular response) cells, will identify the cellsurface antigens of a foreign cell or an engrafted tissue as foreign.This recognition leads ultimately to an immune response against the cellor tissue, resulting in destruction of the cell or rejection of thegraft. An immune response against an allogeneic tissue is known ashost-versus-graft rejection.

Immunologically compromised. An “immunologically compromised” subjecthas a genotypic or a phenotypic immunodeficiency. Agenotypically-immunodeficient subject has a genetic defect that resultsin an inability to generate either humoral or cell-mediated responses. Aspecific, non-limiting example of a genotypically immunodeficientsubject is a genotypically immunodeficient mouse, such as a SCID mouseor a bg/nu/xid mouse (Andriole et al., J. Immunol. 135:2911, 1985;McCune et al., Science 241:1632, 1988) or an XSCID human. A“phenotypically-immunodeficient subject” is a subject, which isgenetically capable of generating an immune response, yet has beenphenotypically altered such that no response is seen. In one specific,non-limiting example, a phenotypically-immunodeficient recipient isirradiated. In another specific, non-limiting example, aphenotypically-immunodeficient subject has been treated withchemotherapy. In yet another specific, non-limiting example, thephenotypically-immunodeficient subject has suffered a bacterial or viralinfection, such as the human immunodeficiency virus (HIV) or simianimmunodeficiency virus (SIV).

Increase: A significant increase in a particular activity or of acomponent of interest. In one embodiment, inhibition refers to at leastabout a 25%, 50%, 60%, 70%, 80%, 90%, 95% or 100% increase in activityor concentration.

Inhibit. A decrease in a particular parameter of a cell or organism. Inone embodiment, inhibition refers to a 25%, 50%, or 100% decrease in aparameter.

Isolated. An “isolated” biological component (such as a nucleic acidmolecule, polypeptide, polysaccharide, selectin, selectin ligand, orother biological molecule) has been substantially separated or purifiedaway from other biological components of cells in which the componentnaturally occurs. An “isolated” cell has been substantially separated orpurified away from other cells of different species (in the case ofmicroorganisms) or cells of the organism (in the case of multi-cellularorganisms). Nucleic acids and proteins may be isolated by standardpurification methods, recombinant expression in a host cell, orchemically synthesized. Cells may be isolated by standard culturingmethods. In one embodiment, the blue-green algae is harvested from anatural source (such as Klamath Lake), and prepared by drying (seebelow).

Leukocytes. White blood cells. Spherical, colorless, and nucleatedcorpuscles involved in host defense, including immunological responses.Specific types of leukocytes include basophils, coelomocytes,eosinophils, haemocytes, lymphocytes, neutrophils, and monocytes,circulating dendritic cells, and circulating hematopoietic stem cells.

L-selectin. A member of the selectin family calcium-dependent lectins,also known as CD62L. An adhesion molecule used by stem cells to adhereto the bone marrow environment. L-selectin, the smallest of the vascularselectins, is a 74-100 kDa molecule, that is constitutively expressed atthe tips of microfolds on granulocytes, monocytes, and a vast array ofcirculating lymphocytes L-selectin is also known as LECAM-1, LAM-1,Mel-14 antigen, gp90^(mel), and Leu8/TQ-1 antigen. L-selectin is knownto be important for binding of leukocytes to endothelium in variousphysiological situations, including binding of phagocytes toendothelium, binding of leukocytes to inflamed endothelium, andlymphocyte homing and adhesion to high endothelial cells of postcapillary venules of peripheral lymph nodes. Moreover, this adhesionmolecule contributes greatly to the capture of circulating leukocytesduring the early phases of the adhesion cascade. The amino acidsequences of many L-selectins are known.

An “L-selectin ligand” specifically binds L-selectin. In someembodiments, a ligand can block activation by other ligands, for exampleby spatial interference with the ligand binding area. A ligand can alsoactivate the cell via ligation to L-selectin, for example by triggeringcalcium flux, cytoskeletal rearrangements, or other signaling events. Inaddition, a ligand can alter signal transduction pathways so asubsequent binding with either another L-selectin ligand, or anL-selectin-independent stimulus results in an altered physiologicalresponse. In some examples, when human lymphocytes are activated viasome L-selectin ligands, L-selectin triggers the expression of CXCR4, areceptor for Stromal Derived Factor 1 (SDF1), a cytokine involved in theresidence of stem cells in the bone marrow. In one embodiment, theL-selectin-containing extract of the blue-green algae inhibited theexpression of CXCR4 triggered by the activation of L-selectin withFucoidan. Amino acid sequences for exemplary L-selectin ligands areknown. For example, Mus musculus GlyCam-1 is shown in GENBANK AccessionNumber NM_(—)008134 and Human mRNA isolates for GlyCam-1 are shown inGENBANK Accession Nos. AJ_(—)489 590, AJ 489 591, AJ 489 592, AJ 489593, and AJ 489 589, all as available on Jun. 24, 2005, which areincorporated herein by reference. These amino acid sequences are notmeant to be limiting, but are provided as examples. Recombinant andmodified forms are included in the present disclosure.

Lymphocytes. A type of white blood cell that is involved in the immunedefenses of the body. There are two main types of lymphocytes: B celland T cells.

Lymphoproliferation. An increase in the production and/or division oflymphocytes.

Mammal. This term includes both human and non-human mammals. Similarly,the term “subject” includes both human and veterinary subjects.

Monocyte. A large white blood cell in the blood that ingests microbes orother cells and foreign particles. When a monocyte passes out of thebloodstream and enters tissues, it develops into a macrophage.

Muscle cell. A cell of striated, cardiac, or smooth muscle tissue. Instriated (skeletal) muscle, a muscle cell is composed of a syncytiumformed by the fusion of embryonic myoblasts. In smooth muscle, a musclecell is a single cell characterized by large amounts of actin and myosinand capable of contracting to a small fraction of its overall length. Incardiac muscle, the muscle cell is linked to neighboring cells byspecialized junctions called intercalated discs.

Pharmaceutically acceptable carriers. The pharmaceutically acceptablecarriers useful are conventional. Remington's Pharmaceutical Sciences,by E. W. Martin, Mack Publishing Co., Easton, Pa., 15th Edition (1975),describes compositions and formulations suitable for pharmaceuticaldelivery of the blue-green algae and extracts described herein.

In general, the nature of the carrier will depend on the particular modeof administration being employed. For instance, parenteral formulationsusually comprise injectable fluids that include pharmaceutically andphysiologically acceptable fluids such as water, physiological saline,balanced salt solutions, aqueous dextrose, glycerol or the like as avehicle. For solid compositions (e.g., powder, pill, tablet, or capsuleforms), conventional non-toxic solid carriers can include, for example,pharmaceutical grades of mannitol, lactose, starch, or magnesiumstearate. In addition to biologically-neutral carriers, pharmaceuticalcompositions to be administered can contain minor amounts of non-toxicauxiliary substances, such as wetting or emulsifying agents,preservatives, and pH buffering agents and the like, for example sodiumacetate or sorbitan monolaurate.

Plasticity. The capability to be molded, often used to refer to theglexibility and reversibility of tissue and lineage specification

Platelets. Small cell fragments in blood derived from megacaryocytes.Platelets participate in wound healing, blood clotting, repair ofdamaged blood vessels and pathological inflammatory processes.

Progenitor cell. A cell that gives rise to progeny in a defined celllineage. A “hematopoietic progenitor cell” is a cell that gives rise tocells of the hematopoietic lineage.

P-selectin. A member of the selectin family calcium-dependent lectins,also known as CD62P. P-selectin is expressed on the surface ofendothelial cells, platelets (increased amounts with activation), andmegacaryocytes. P-selectin can mediate binding of activated platelets toleukocytes, and can further contribute to subsequent binding of theseleukocytes to endothelium. P-selectin expression on bone marrowendothelium plays a role for stem cell locations in vivo, including bonemarrow retention, mobilization and homing (Frenette and Weiss, Blood96(7): 2460, 2000).

Recruitment of a stem cell. A process whereby a stem cell in thecirculatory system migrates into a tissue or organ. Recruitment may befacilitated by a compound or molecule, such as a chemoattractant signalor cell receptor. For example, both CXCR4 and SDF-1 have identifiedroles in stem cell homing. Hidalgo et. al., Exp. Hematol. 29(3):345-55,2001; Kollet et al., Blood 97(10)3283-91, 2001.

Satellite cell. A muscle-specific stem cell, often located in theperiphery of muscle tissue, and capable of migrating into a muscle toaid in tissue repair and reconstruction.

Selectin. A family of calcium-dependent lectins, also known as CD62. Thethree members of this family include L-selectin (CD62L), P-selectin(CD62P), and E-selectin (CD62E). These adhesion molecules are involvedin slowing circulating leukocytes during their transit in venules, andare also involved in a host of other adhesive interactions, includingbut limited to platelet-leukocyte interactions, cell retention incertain tissues including bone marrow, and adhesion of leukocytes toinflamed endothelium.

Stem cell. A pluripotent cell that gives rise to progeny of many tissuetypes, including (but not limited to) the entire hematopoietic andmarrow stromal cell lineages. A typical stem cell resides in the bonemarrow, either as an adherent stromal cell type, or as a moredifferentiated cell that expresses CD34, either on the cell surface orin a manner where the cell is negative for cell surface CD34. Stem cellscan also express CD133. Thus a stem cell can be a CD34+ cell, a CD133+cell, or can be shown to express both CD34 and CD133 (see He et al.,Stem Cells and Development 14(2):188-198, 2005). Alternatively, a stemcell can be a cell that can be measured by fluorescently labeledaminoacetaldehyde, formed when an enzyme in stem cell cytoplasm,converts a non-fluorescent substrate into a fluorescent compound that isretained inside the stem cell and allowing its detection based onenzymatic function.

A subset of CD34⁺ cells in bone marrow, leukapheresis products and cordblood with primitive phenotypic characteristics express CD133, a5-transmembrane molecule of unknown function. Antibodies specific forCD133 stain 35-75% of the CD34⁺ population depending on the source ofstem cells (De Wynter et al., Stem Cells 16:387-396, 1998).Transplantation of an isolated CD133⁺ CD34⁺ non-adherent stem cellfraction into immunodeficient NOD/SCID mice induced high myeloid andlymphoid multilineage engraftment, suggesting that these cells arehighly enriched in SCID-repopulating cells (Kuci et al. Blood101:869-876, 2003).

“Totipotent” stem cells, such as hematopoietic stem cells or neuronalstem cells, generally give rise to progeny of a limited number of tissuetypes. Hematopoietic stem cells, muscle stem cells and neuronalprecursor cells are several examples of totipotent stem cells.

Subject. An animal that has a circulatory system, including vertebratessuch as humans and other veterinary subjects, such as, but not limitedto, primates, canines, felines, bovines, and rodents.

Trafficking. The processes of movement of a cell from the tissue oforigin and traveling within the circulatory system. In one embodiment,trafficking includes movement of a cell from the tissue of origin,homing by adhesion to the endothelium, transmigration, and finalmigration within the target organ. In one embodiment, tracking is theprocess of movement of a cell of the immune system. In anotherembodiment, trafficking includes stem cell mobilization. One specific,non-limiting example of trafficking is the movement of a stem cell to atarget organ. Another specific, non-limiting example of trafficking isthe movement of a B cell or a pre-B cell leaving the bone marrow andmoving to a target organ.

Transdifferentiation. The change of a cell or tissue from onedifferentiated state to another, or the differentiation of atissue-specific stem cell into another type of cell as, for example, abone marrow stem cell differentiating into a neuron.

Transplantation. The transfer of a cell population, tissue or an organ,or a portion thereof, from one body or part of the body to another bodyor part of the body. An “allogeneic transplantation” or a “heterologoustransplantation” is transplantation from one individual to another,wherein the individuals have genes at one or more loci that are notidentical in sequence in the two individuals. An allogeneictransplantation can occur between two individuals of the same species,who differ genetically, or between individuals of two different species.An “autologous transplantation” is a transplantation of a tissue or aportion thereof from one location to another in the same individual, ortransplantation of a tissue or a portion thereof from one individual toanother, wherein the two individuals are genetically identical.

Unless otherwise explained, all technical and scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which this disclosure belongs. The singular terms“a,” “an,” and “the” include plural referents unless context clearlyindicates otherwise. Similarly, the word “or” is intended to include“and” unless the context clearly indicates otherwise. It is further tobe understood that all base sizes or amino acid sizes, and all molecularweight or molecular mass values, given for nucleic acids or polypeptidesare approximate, and are provided for description. Although methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of this disclosure, suitable methods andmaterials are described below. The term “comprises” means “includes.”All publications, patent applications, patents, and other referencesmentioned herein are incorporated by reference in their entirety. Incase of conflict, the present specification, including explanations ofterms, will control. In addition, the materials, methods, and examplesare illustrative only and not intended to be limiting.

Selectin Ligand Isolated from Blue-Green Algae Cells

Disclosed herein is an aqueous extract of blue-green algae, such asAphanizomenon flos aquae (AFA), that is enriched for a selectin ligand,such as an L-selectin ligand. In one embodiment, the extract is “ExtractA,” an aqueous extract that includes polar compounds rapidly dissolvedin water or saline, which is enriched for a selectin ligand, such as anL-selectin ligand. In another embodiment, this extract is dried using aknown process, and re-suspended in an aqueous solution.

Blue-Green Algae, such as Aphanizomenon flos aquae (AFA) or Spirulinacan be fractionated. Process for growing, harvesting, and concentratingblue-green algae cells have been described. Blue-green algae, such asAFA or Spirulina, can be isolated from any source. The source can be anatural source of blue-green algae, such as a lake (for example KlamathLake). The source can also be a man-made source of blue-green algae suchas an artificial lake or water source. The source can be an environmentproduced to grow and harvest blue-green algae commercially.

The blue-green algae can be used directly, or can be stored as liquid,frozen liquid, freeze-dried, or dried using the method described below.In one embodiment, the blue-green algae are harvested and dried usingREFRACTANCE WINDOW™ Technology. The term “REFRACTANCE WINDOW™Technology” refers to a system wherein the dryer utilizes the veryproperties of water to drive water out of the product. In brief, whenwater is placed over a heating source, heat gets dispersed in the waterthrough convection. As it absorbs heat, water transmits infrared energyto the outside in three ways: evaporation, conduction, and radiation. Ifthe surface of the water surface is covered by a transparent medium suchas plastic, evaporation and its associated heat loss are blocked andonly conduction occurs. The plastic membrane acts like a mirrorreflecting infrared energy. When a moist material, such as wetblue-green algae is placed on the plastic surface, the water in thematerial creates a “window” that allows for the passage of infraredenergy. It is believed that in this system the water in the materialallows for radiation, conduction and evaporation all to occur, providingfor exceptionally effective heat transfer. However after a few minutes,as the material dries, the infrared “window” closes and conductionremains the only means of heat transfer. Since plastic is a poor heatconductor, little heat is lost and transferred to the product.Therefore, when dried with REFRACTANCE WINDOW™ Technology, algae areexposed to heat only briefly.

In this drying system, liquid algae (cells suspended in solution) areplaced on the surface of the dryer's conveyor belt. The belt is a foodgrade mylar (transparent polyester film) set on the surface of hotwater. Heat from the circulating water is conducted to the belt and theninto the water present in the product to be dried, gently speeding thenatural process of evaporation while protecting natural nutrients. Asthe product dries and water evaporates, heat ceases to be transmitted tothe product. Without being bound by theory, this prevents thedegradation of polypeptides, nucleic acids, nutrients and pigments.Thus, the drying process maintains algae temperature far below thetemperature of the circulating water beneath the conveyor belt.

Other drying systems can be used to produce dried algae. Generally, twofactors play a role in the degradation of algae: degree of heat andexposure time to heat. Applying a high amount of heat for a short periodof time results in less degradation of the components of the blue-greenalgae. In one example, heat, such as a temperature of about 65° C. toabout 80° C. is applied, such as a temperature of about 70° C. to about75° C., or about 72° C. The heat can be applied for a sufficient amountof time to dry the algae, such as about 1 to about 15 minutes, or forabout 2 to about 10 minutes, or for about 3 to about 7 minutes. In oneexample, heat is applied to the algae at 72° C. for only 3 to 5 minutes.This process is known to one of skill in the art, and is fully describedat the Rossha Enterprises Website, and is described in Abonyi et al.,“Evaluation of Energy Efficiency and Quality Retention for theREFRACTANCE WINDOW™ Drying System: Research Report,” Washington StateUniversity, Pullman, Wash., Dec. 30, 1999). However, freeze dried cellscan also be utilized.

As disclosed herein, an aqueous extract can be prepared from fresh,dehydrated, or preserved blue-green algae cells, such as Aphanizomenonflos aquae (AFA). The algae can be extracted with water or a suitablebuffered salt solution. For example, water or buffered solutions,general of a neutral pH (about pH 7.0 to about pH 7.8, such as about pH7.2 to about pH 7.6, or about pH 7.4) is utilized. Suitable bufferedsalt solutions are well known in the art and include phosphate bufferedsaline (such as about 0.1 M phosphate buffered saline) and commerciallyavailable culture media. The aqueous extraction is generally performedbelow room temperature (generally 25° C.), such as at temperatures ofabout 3° C. to about 15° C., such as at about 4° C. to about 10° C., orat about 4° C., but the extraction can also be performed at roomtemperature (about 25° C.).

In one example, one gram of dried algal material, such as driedAphanizomenon flos aquae (AFA), is suspended in about 10 ml to about 50ml, such as about 40 ml of phosphate-buffered saline (for example, 0.1 Mphosphate buffered saline, pH. 7.4), and incubated at 4° C. Thisincubation can last for 5 minutes, half an hour, several hours, orovernight. In several examples, the algae is incubated in an aqueoussolution for about half an hour to about two hours, about half an hourto about three hours, or about half an hour to about 12 hours. The algaesuspended in the buffered salt solution can be protected from light todecrease degradation. Following incubation in an aqueous solution, thesolid material is separated from the aqueous extract. The mixture ofalgae in the aqueous solution, such as the salt solution, can be mixedby repeated inversion of the vial, and centrifuged to remove solidmaterial. For example, the suspension can be centrifuged at 400 g for 10minutes.

Following separation of the solid material, the supernatant, whichgenerally appears blue in color, is isolated. This extract is termed“Extract A.” This supernatant optionally can be sterilized, such as byfiltration. In one example, a bright blue supernatant is decantedfollowing centrifugation and sterile filtered using a 0.22 mm filter.This filtrate can be stored, such as at about 4° C. in the dark.

The extract that contains the selectin ligand, such as the L-selectinligand, such as Extract A, can be dried, as described above. In oneexample, heat, such as a temperature of about 65° C. to about 80° C. isapplied to the aqueous extract, such as a temperature of about 70° C. toabout 75° C., or about 72° C. The heat can be applied for a sufficientamount of time to dry the extract, such as about 1 to about 15 minutes,or for about 2 to about 10 minutes, or for about 3 to about 7 minutes.In one example, heat is applied to the extract at 72° C. for only 3 to 5minutes. This process is similar to the process for drying algae (seeAbonyi et al., “Evaluation of Energy Efficiency and Quality Retentionfor the REFRACTANCE WINDOW™ Drying System: Research Report,” WashingtonState University, Pullman, Wash., Dec. 30, 1999). One of skill in theart can readily produce a dried product from an aqueous extract usingknown methodologies.

In several specific, non-limiting, examples an effective amount of theselectin-containing extract of blue-green algae, such as an aqueousextracted enriched for an L-selectin ligand, is from about 0.25 gram toabout 5 gram, or from about 0.5 gram to about 5 gram, or from about 1gram to about 2 gram of a dried aqueous extract, such as extract A. Inone specific, non-limiting example, the effective amount ofselectin-containing extract of blue-green algae is about 1 gram of adried aqueous extract, such as extract A.

A selectin ligand can be further purified from the aqueous extract A.For example, the selectin ligand is isolated using affinitypurification. In one example, Extract A is contacted with a solidsubstrate including L-selectin, P-selectin, or E-selectin. Magneticbeads covalently bound to a selectin, such as human L-selectin can beutilized. An exemplary amino acid sequence of human L-selectin is setforth as GENBANK Accession No. NP_(—)000646; an exemplary amino acidsequence of murine L-selectin is set forth as CAB55488 and an exemplarysequence of mouse L-selectin is set forth as GENBANK Accession No.AAH52681. All of these sequences were available on the internet on Jun.24, 2005, and are incorporated by reference herein. Additional exemplarysequences of L-, P-, and E-selectins can be found in the GENBANKdatabase.

The selectin can be a native molecule, such as a human L-selectin, ahuman P-selectin, a murine L-selectin, or a murine P-selectin. Theselectin can also be a genetically engineered form, such as arecombinant molecule that is a stable form of the L-selectin, and/or amolecule that includes a fragment of a selectin, such as theextracellular portion of the human L-selectin molecule. In one example,the selectin is a fusion protein in which the extracellular portion ofhuman L-selectin and the Fc portion of immunoglobulin. Such recombinantfusion proteins are commercially available, such as from, for example,R&D Systems, and can be ordered through the internet. The solidsubstrate covalently bound to the selectin, such as, but not limited to,L-selectin, is incubated with the supernatant “Extract A” (thewater-soluble extract of the blue green algae).

The material from the algae that specifically binds a selectin is thenisolated. For example, the selectin ligand can cleaved from therecombinant selectin molecule using an acid treatment. The selectinligand can also be cleaved from the recombinant selectin molecule usingan alkaline treatment and/or using heat treatment.

As disclosed herein, the isolated selectin ligand has a molecular weightof about 50 kDa to about 60 kDa, such as about 55 kDa, under reducingconditions. In one example, the isolated selectin ligand has a molecularweight of about 54 kDa or about 57 kDa under reducing conditions. In oneembodiment, the selectin ligand does not form a complex. For example,the selectin ligand can not form a complex with itself or with anotherselectin ligand.

In several examples, under non-reducing conditions, the selectin ligandcan associate into a complex. Thus, if a complex of three 54 kDasubunits is formed under non-reducing conditions the molecular weight isabout 162 kDa, and if a complex of three 57 kDa subunits is formed theapparent molecular weight under non-reducing conditions is about 171kDa. If a complex of three 54 kDa subunits and three 57 kDa subunits isformed under non-reducing conditions the molecular weight of the complexis about 233 kDa. Thus, the purified selectin ligand can have amolecular weight of about 200 kDa under non-reducing conditions. If acomplex of one of each ligand is formed, then the apparent molecularweight of the complex is approximately about 111 kDa. Alternatively, thetwo subunits can not be in a complex, and the apparent molecular weightunder non-reducing conditions will be the same as under reducingconditions. The selectin ligand can be a protein or a glycoprotein.

The extracts and compositions disclosed herein can be administered inany form, including as solids such as tablets or powders or as a liquidpreparation. In one example, the compositions are formulated for enteraladministration. An example of a formulation of use is a pharmaceuticalpreparation (such as a tablet, enteral liquid, parenteral liquid,capsule, intranasal liquid or other form). In a particular disclosedexample the composition is a pharmaceutical preparation, in particular atablet or capsule. As is known in the art, compositions suitable fororal administration may be presented as discrete units such as capsules,cachets, or tablets, each containing a therapeutically effective amountof the composition, as a powder or granules, or as a solution or asuspension in an aqueous liquid. Thus, dosage forms include tablets,capsules, dispersions, suspensions, solutions, capsules and the like.Because of their ease of administration, tablets and capsules representa convenient oral dosage unit form, in which case solid pharmaceuticalcarriers as described above are employed. However, the compounds canalso be administered by controlled release means, or can be formulatedfor other means of delivery, such as, but not limited to intranasal ortransdermal delivery.

The compositions can include inactive ingredients such as binding agents(such as pregelatinized maize starch, polyvinylpyrrolidone orhydroxypropyl methylcellulose); binders or fillers (such as lactose,pentosan, microcrystalline cellulose or calcium hydrogen phosphate);lubricants (such as magnesium stearate, talc or silica); disintegrants(such as potato starch or sodium starch glycolate); or wetting agents(such as sodium lauryl sulphate).

In one example, a tablet containing the compositions disclosed herein,such as but not limited to an extract enriched for an L-selectin ligandor a solid form thereof, or a purified selectin ligand, can be preparedby compression or molding, optionally, with one more accessoryingredients. Compressed tablets can be prepared by compressing in asuitable machine, a free-flowing form such as powder or granules of adried extract and/or selectin ligand, optionally mixed with a binder,lubricant, inert diluent, surface active or dispersing agent. Thecomposition, such as the tablet, can include pharmaceutically acceptablecomponents such as lactose, glucose, sucrose, corn starch, potatostarch, cellulose esters such as cellulose acetate, ethyl cellulose,magnesium stearate, calcium silicate, precipitated silica, talc, fattyacids such as stearic acid, microcrystalline cellulose, carnauba wax andthe like. The tablets or capsules can be coated by methods well known inthe art.

Liquid preparations for oral administration can take the form of, forexample, solutions, syrups or suspensions, or they can be presented as adry product for constitution with water or other suitable vehicle beforeuse (see the examples section). Such liquid preparations can be preparedby conventional means with pharmaceutically acceptable additives thatare inactive agents, such as suspending agents (such as sorbitol syrup,cellulose derivatives or hydrogenated edible fats), emulsifying agents(such as lecithin or acacia), and preservatives (such as methyl orpropyl-p-hydroxybenzoates or sorbic acid). The compositions can also bemade to be pleasant tasting, and thus can contain buffer salts,flavoring, coloring and sweetening agents as appropriate.

Diluents and other inactive ingredients such as one or morepharmaceutically acceptable binding agents, fillers, supports,thickening agents, taste-improving agents, coloring agents,preservatives, stabilizers, regulators, emulsifiers, flow agents,absorbents, and the like or mixtures thereof may be used depending onthe form of the composition employed. The composition can also include asweetener, such as a natural (for example, sugar or honey) or artificialsweetener (for example, saccharine), if desired. Generally, thecarriers, sugars, diluents, stabilizers, buffers, flavoring andtexturing ingredients are considered to be inactive ingredients, as theydo not impart a therapeutic effect in and of themselves.

In several embodiments, the composition can include one or moreadditional extract(s) of Aphanizomenon flos aquae (AFA) that induces themigration of stem cells. This extract can be obtained by extractingliquid Aphanizomenon flos aquae (AFA) in an alcohol, such as but notlimited to, ethanol or methanol. In one example, the additional extractis produced by extracting Aphanizomenon flos aquae (AFA) in about 10% toabout 20% ethanol. In one example, the composition includes an extractprepared by extracting liquid Aphanizomenon flos aquae (AFA) in about10% ethanol. In one example, the additional extract is produced byincubating liquid AFA in about 10% ethanol at a temperature of about 65°C. to about 85° C. is applied to the aqueous extract, such as atemperature of about 70° C. to about 905° C., or about 85° C. Thesolution is then centrifuged and the supernatant is dried (see above).In one embodiment, about 50 mg to about 500 mg, such as about 100 mg toabout 250 mg, such as about 150 mg of the dried product is administeredto the subject.

In one example, a composition of use includes about 0.25 gram to about 5gram, of from about 0.5 gram to about 5 gram, or from about 1 gram toabout 2 gram of a dried selectin-containing extract, such as a solidform of an aqueous extract enriched for an L-selectin ligand, such asextract A. In one specific, non-limiting example, the compositionincludes about 1 gram of a dried selectin-containing extract ofblue-green algae (such as AFA), such as a solid form of an aqueousextract enriched form an L-selectin ligand, such as extract A. Thecomposition also includes about 150 mg of a second dried extract of AFA, wherein the second dried extract is produced by incubating AFA inabout 10% to about 20% ethanol at about 70° C. to about 90° C. for aboutone to three hours, such as by incubating AFA in about 10% ethanol forat about 850° C. for about one to three hours.

Enhancing Stem Cell Mobilization

A method is described herein for enhancing stem cell mobilization byadministering to a subject a therapeutically effective amount of anaqueous extract of a blue green algae such as Aphanizomenon flos aquae(AFA), enriched for a selectin ligand, such as L-selectin, and/or atherapeutically effective amount of a purified selectin-ligand. Theselectin ligand can be an L-selectin, P-selectin, and/or an E-selectinligand. Selectin ligands stimulate stem cell release (Frenette andWeiss, Blood 196(7): 2460, 2000). The subject can be any subject, suchas a human or a veterinary subject.

An aqueous extract of blue-green algae enriched for a selectin ligand,such as an L-selectin, or a purified selectin-ligand from blue-greenalgae, can be administered alone or in combination with other agents. Inseveral embodiments, the purified selectin ligand and/or the aqueousextract enriched for a selectin ligand (or a solid form thereof), isincluded in a pharmaceutical composition along with a pharmaceuticallyacceptable carrier. Therapeutically effective amounts of additionalcomponents, such as solid forms of additional extracts, can also beadministered to the subject. In one embodiment, a therapeuticallyeffective amount of a solid form of an aqueous extract of a blue greenalgae enriched for a selectin ligand is administered to the subject.Thus, a method is provided herein for increasing the mobilization ofstem cells in a subject, comprising administering a therapeuticallyeffective amount of an aqueous extract of blue-green algae enriched fora selectin ligand, such as L-selectin, thereby increasing themobilization of stem cells in the subject.

In one specific, non-limiting example, the aqueous extract is dried,such that a solid form is produced, and a therapeutically effectiveamount of the solid form is administered to a subject of interest. Thetherapeutically effective amount of the extract, such as an aqueousextract of blue-green algae enriched for a selectin ligand, is fromabout 0.01 to about 1.0 g per kg body weight, such as about 0.05 toabout 0.5 gram per kg body weight, or from about 0.1 to about 0.5 gramper kg body weight. In another specific, non-limiting, example theeffective amount of the solid form of an aqueous extract of blue-greenalgae enriched for a selectin ligand is from about 0.25 gram to about 5gram, of from about 0.5 gram to about 5 gram, or from about 1 gram toabout 2 gram. In one specific, non-limiting example, the effectiveamount of the solid form of the aqueous extract of blue-green algaeenriched form a selectin ligand is about 1 gram.

The active agents of the compositions disclosed herein can be admixedwith a carrier. In general, the nature of the carrier will depend on theparticular mode of administration being employed. For instance,parenteral formulations usually comprise injectable fluids that includepharmaceutically and physiologically acceptable fluids such as water,physiological saline, balanced salt solutions, aqueous dextrose,glycerol or the like as a vehicle. For solid compositions (e.g., powder,pill, tablet, or capsule forms), conventional non-toxic solid carrierscan include, for example, pharmaceutical grades of mannitol, lactose,starch, or magnesium stearate. In addition to biologically-neutralcarriers, pharmaceutical compositions to be administered can containminor amounts of non-toxic auxiliary substances, such as wetting oremulsifying agents, preservatives, and pH buffering agents and the like,for example sodium acetate or sorbitan monolaurate.

This effective amount may be administered at a given frequency, such asabout once a week, about twice a week, about three times a week, once aday, about twice a day, about three times a day, or more. One of skillin the art can readily determine a therapeutically effective amount of apurified selectin ligand, or an aqueous extract enriched from a selectinligand. In one specific, non-limiting example, the amount of circulatingstem cells, such as the amount of cell expressing CD34, is assessed.

The therapeutically effective amount of an aqueous extract blue-greenalgae enriched for a selectin ligand and the frequency of administrationof these compositions, can depend on a variety of factors, such as thegenus or species of algae utilized, the general health of the subjectbeing treated, and the physiological characteristics (e.g., height,weight, body fat percentage, metabolism, etc.) of the subject beingtreated. The aqueous extract can be administered directly, withoutaltering the physical parameters, or can be administered in anotherphysical form. Thus, in one embodiment, the extract is dried and isadministered as a solid. In another embodiment, the aqueous extract isdried, and then a specific amount is dissolved in a carrier andsubsequently administered to the subject.

Specific assays for determining a therapeutically effective amount of anaqueous extract, such as an aqueous ligand enriched for a selectin areprovided herein. In one specific, non-limiting example, differentamounts of a selectin ligand-containing extract of blue-green algae,such as AFA, are consumed by human subjects and the presence and/orquantity of stem cells (which can include subtypes of such cells)present in the circulatory system is detected and/or analyzed. Inanother embodiment, an animal (such as a mouse, rat, or otherveterinary) model is utilized, and the population of newly integratedstem cells is monitored in various tissues (see the Examples below). Itshould be noted that the methods disclosed have equal application inmedical and veterinary settings.

Regardless of how provided or administered, the blue-green algae extractand/or purified selectin ligand induce a transient increase in thepopulation of circulating stem cells, such as CD34+ stem cells and/orCD133+ cells. The blue-green algae extract can also include a transientincrease in stem cells that can be measured by fluorescently labeledaminoacetaldehyde. This procedure is described on the stem cell website(see http://www.stemcell.com/technical/aldefluor.asp, see alsohttp://www.stemcell.com/technical/12_aldefluor.pdf). Briefly,fluorescent-labeled aminoacetaldehyde can freely diffuse into cells. Anintracellular enzyme ALDH (aldehyde dehydrogenase) converts this intofluorescent-labeled aminoacetate, which cannot diffuse out of the cells.Thus, cells that have the enzyme ALDH (such as stem cells) becomefluorescent. Other cells (such as cells that are not stem cells,including differentiated cells) appear non-fluorescent after washing.

Enhancement of stem cell mobilization may be measured by assaying theresponse of stem cells to a particular dose of blue-green algae extract.In one embodiment, providing a purified selectin-ligand from blue-greenalgae to a subject will enhance mobilization of that subject's stemcells within a certain time period, such as less than about 5 hours,less than about 4 hours, less than about 2 hours, less than about 1hour, less than about 30 minutes, or less than about 10 minutesfollowing administration.

In one embodiment, administration of the aqueous extract of blue-greenalgae enriched for a selectin ligand, and/or the purified selectinligand, results in the mobilization of stem cells into the circulationfrom about 10 to about 30 minutes following administration. Mobilizedstem cells will enter the circulatory system, thus increasing the numberof circulating stem cells within the subject's body. The percentageincrease in the number of circulating stem cells compared to a normalbaseline may about 25%, about 50%, about 100% or greater than about 100%increase as compared to a control. In one embodiment, the control is abaseline value from the same subject. In another embodiment, the controlis the number of circulating stem cells in an untreated subject, or in asubject treated with a placebo or a pharmacological carrier.

In some embodiments, the subject is healthy. In other embodiments, thesubject is suffering a disease or physiological condition, such asimmunosuppression, chronic illness, traumatic injury, or degenerativedisease. In certain embodiments, the subject suffers a disease orcondition of the skin, digestive system, nervous system, lymph system,cardiovascular system, or endocrine system. In specific embodiments, thesubject suffers osteoporosis, Alzheimer's disease, cardiac infarction,Parkinson's disease, traumatic brain injury, multiple sclerosis,cirrhosis of the liver, or any of the diseases and conditions describedin the Examples below.

EXAMPLES

The following examples are provided to illustrate particular features ofvarious described embodiments. The scope of the present invention shouldnot be limited to those features exemplified.

Example 1 Production of AFA and Extraction

A blue-green algae, Aphanizomenon flos aquae (AFA), was isolated fromKlamath Lake. The blue-green algae was dried using REFRACTANCE WINDOW™Technology.

One gram of dried algal material was resuspended in 10 mlphosphate-buffered saline or water and incubated 1 hour at 4° C. andprotected from light. This slush was mixed by repeated inversion of thevial, and centrifuged at 400 g for 10 minutes. The bright bluesupernatant was decanted and sterile filtered using a 0.22 mm filter.This filtrate was stored cold and dark, and used within the same day ofpreparation. This extract was called Extract A

Example 2 Selectin Ligand Extracted from AFA-W: Materials and Methods

Buffers and media: For cell cultures, cells were re-suspended andcultured in RPMI-1640 with 10% fetal calf serum, 1% penicillin andstreptomycin, and L-glutamine. For immunostaining, cells were washed,resuspended, and stained in phosphate-buffered saline containing 0.02%Azide and 1% fetal calf serum or bovine serum albumin. For proliferationassays and for stimulation for phosphotyrosine blotting assays, cellswere prepared in RPMI 1640 with phenol red, 10% Fetal Calf Serum (Gibco,Grand Island N.Y.), 1% glutamine, 1% Penicillin and 1% Streptomycin.

Cyanobacterial extracts: Dried powder of the freshwater blue-green algaeAphanizomenon flos aquae (AFA) was obtained from Upper Klamath Lake inOregon, USA. For early experiments, a freeze-dried powder was used. Forlater experiments, a powder was obtained from Desert Lake TechnologiesLLC, Keno, Oreg., which had been dried using the REFRACTANCE WINDOW™0drying technology. Dried powder of Spirulina platensis was obtained fromHealthforce Nutritionals Inc, Escondido Calif. One gram of dried algalmaterial was resuspended in 10 ml phosphate-buffered saline, andincubated overnight at 4° C. and protected from light. The slush wasmixed by repeated inversion of the vial, and centrifuged at 400 g for 10minutes. The bright blue supernatant was decanted and sterile filteredusing a 0.22 mm filter. This filtrate was stored cold and dark, and usedwithin the same day of preparation.

Monoclonal antibodies: The CD62L monoclonal antibody TQ1 (specific forthe ligand-binding area of the L-selectin molecule) linked tophycoerythrin (PE), was purchased from Coulter (Hialeah, Fla.).CD45-PerCP, CD11b-PE, CD14-PE, and isotype control antibodies wereobtained from Becton-Dickinson.

Capturing of ligand using Dynabeads and chimera proteins: In order toidentify the molecular weight of the selectin binding compound, acell-free method was used, in which Dynabeads (Dynal Biotech Inc., LakeSuccess, N.Y.) coated with Protein G were incubated with a selectinchimera protein (R & D Systems Inc., Minneapolis, Minn.). The chimeraprotein is a fusion of the extracellular domain of human L-selectin,P-selectin, or E-selectin, with the Fc portion of human immunoglobulinG. The chimera protein was covalently linked onto the Protein G-coatedDynabeads using the protocol recommended by the manufacturer, in whichbeads were incubated for 1 hour in a freshly made 5.4 mg/ml solution ofdimethyl pimelimidate×2HCl (Sigma Aldrich) in 0.2 M triethanolaminebuffer pH 8.0 (Sigma Aldrich). The cross-linking was stopped by removingthe beads from the cross-linking solution, and resuspending in 50 mMTRIS buffer pH 7.5 (Sigma Aldrich) for 15 minutes. Unbound chimera waseluted off the beads by two washes in citrate/citric acid buffer pH 2.8.The beads were then washed several times in PBS pH 7.4, and added to afreshly made AFA water extract. Bound material from the AFA waterextract was eluted in one of three ways: 1) by boiling in Laemmli buffercontaining beta-mercaptoethanol, 2) eluting with pH 12.5, and 3)competition for the selectin ligand binding site using known selectinligands. It was found that a compound of apparently identical molecularweight was affinity purified by both L-selectin and P-selectin.

In parallel experiments, beads coated with recombinant humanL-selectin/IgG1 fusion protein were used to see whether a similar waterextract from other blue-green algae, Spirulina platensis, contained asimilar selectin-binding compound.

Electrophoresis: Samples of eluant from the Dynabead affinity methodwere prepared for gel electrophoresis by mixing 1:1 v/v in Laemmlisample buffer (Biorad cat# 161-0737) with mercaptoethanol. SDS gelelectrophoresis was performed on 4-15% gels (BioRad) in TRIS/glycine/SDSbuffer (Biorad cat# 161-0732) for 1 hour at 120 V.

Electrophoresis for native protein was performed with SDS-free reagents,using Native Sample Buffer (Biorad cat# 161-0738) for loading, andTRIS/glycine buffer (Biorad cat# 161-0734) for electrophoresis.

Human subjects: Healthy human volunteers were recruited upon informedconsent from laboratory staff and students between 20 and 45 years ofage. Blood samples were obtained by venopuncture under asepticconditions, and processed immediately.

Isolation of Peripheral Blood Mononuclear Cells (PBMC): Peripheralvenous blood was layered onto Ficoll-Hypaque (Amersham), and centrifugedfor 25 minutes at 400 g. The PBMC-rich interface was harvested, and thecells washed twice in RPMI.

Isolation of Polymorph Nucleated Cells (PMN): Peripheral venous bloodwas mixed with dextran70 in 0.9% saline to a final concentration of 1%dextran at room temperature. Sedimentation was allowed for 1 hour. Theleukocyte-rich supernatant was harvested and the leukocytes pelleted bycentrifugation. The pellet was resuspended in 2 ml of phosphate bufferedsaline which was then layered on top of 3 ml Ficoll-Hypaque, andgradient centrifugation performed to separate mononuclear cells(lymphocytes and monocytes) from neutrophils. The pellet containingneutrophils was resuspended in saline. Cells were washed, resuspended ina nutrient-rich medium (RPMI 1640), and kept on ice until use.

Immunostaining for L-selectin: Fresh and formalin-fixed peripheral bloodleukocytes were distributed into wells in a V-bottom 96-well microtiterplate at the approximate concentration of 10⁵ cells per well. A freshlyprepared water-based extract of the blue-green algae AFA was prepared inphysiological saline and serial dilutions performed. Cells wereresuspended in either PBS, PBS-AFA-W, PBS-AFA-W-azide, or PBS-PC atvarious dilutions. Cells were incubated at room temperature and in thedark for 20 minutes. The unfixed fraction was not in contact with sodiumazide during treatment with AFA extract, but was resuspended in sodiumazide-containing buffer for subsequent immunostaining. This was to allowfor free cytoskeletal movements and shedding of L-selectin. The fractionthat was kept in 0.02% sodium azide was in contact with sodium azideduring the whole procedure, both treatment with AFA extract andsubsequent immunostaining. This would block cytoskeletal movement andreduce or block L-selectin shedding. After incubation with or withoutAFA-W, buffer was added, and cells centrifuged. Supernatant wasdiscarded, and cells resuspended in a volume of 50 μl phosphate-bufferedsaline containing 1% fetal calf serum and 0.05% azide. Optimal amountsof monoclonal antibodies, as determined by previous titrations, wereadded. Plates were incubated at room temperature for 10 minutes, bufferwas added, and plates centrifuged. Supernatants were discarded, cellsresuspended in 50 μl buffer, and fixed in 1% formalin. Samples were keptcold and dark until acquisition by flow cytometry. Acquisition wasperformed within 24 hours of fixation.

Immunostaining for CXCR4 expression induced by L-selectin ligands: Thebinding of Fucoidan to L-selectin results in externalization of pre-madeCXCR4 onto the cell surface, followed by internalization, creating awindow in time for responsiveness to chemotactic factors. This systemwas used to examine whether AFA-W would compete with Fucoidan forbinding to L-selectin on the leukocyte cell surface, and to assesswhether it would block this functional effect from another L-selectinligand. To do so, freshly purified human PBMC were resuspended in RPMI,and distributed in a series of round-bottom microwells. Fucoidan wasadded to one series of wells, AFA-W to another series, and a mixture ofFucoidan and AFA-W was added to the third series of wells. At differenttime points (1, 10, 20, 30, 40, 60 minutes), PBS containing sodium azidewas added to wells in order to stop cytoskeletal movements, and therebystop the recycling of CXCR4, allowing staining for CXCR4 expressed atthe cell surface at each time point. Cells were washed inphosphate-buffered saline containing azide, stained with CXCR4-PE usingthe staining protocol described above, fixed in formalin, and analyzedby flow cytometry.

Estimation of molecular weight of native versus denatured components ofthe selectin ligand from AFA: The distances on the gel were measured forthe known molecular weight markers. The position of the AFA-derivedselectin ligand (double band) was plotted onto that graph.

Example 3 Stem Cells are Mobilized by an Aqueous Extract from AFA

This experiments described below demonstrates that an aqueous extract ofAFA (Extract A, also termed “AFA-W”) is enriched for a selectin ligandand can be used to enhance mobilization of CD34+ stem cells.

Healthy human volunteers were identified, and the proportion of CD34+cells was evaluated in the peripheral blood (circulating CD34+ cells) ofeach person prior to consumption of the selectin-containing extract ofblue-green algae as well as 10 minutes, 30 minutes, 60 minutes, and 120minutes after consumption. The volunteers were instructed to limitphysical and mental activity for a time before and after consumption ofthe AFA extract.

In one embodiment, 5 grams of dried AFA was extracted in 40 ml of waterand the participant drank the water. In another embodiment, participantsconsumed 750 mg of dried L-selectin-ligand containing extract of AFA.Red blood cells in whole blood samples obtained from each volunteer werelysed using FACS lysing solution (Beckton-Dickinson, San Jose, Calif.).The remaining cells were washed and stained with monoclonal antibodyHPCA-2 conjugated with fluorescein isothiocyanate. Samples were fixed in1% formalin and analyzed by flow cytometry using a FacsCalibur flowcytometer (Becton-Dickinson, San Jose, Calif.) and CellQuest software(Becton-Dickinson, San Jose, Calif.).

FIG. 1 illustrates that consumption of the selectin-ligand containingextract of AFA triggered a transient increase in circulating stem cells.Specifically, the X-axis shows the time course of a typical experimentat 0, 10, 30, and 60 minutes after ingestion of the L-selectin-ligandcontaining extract of AFA, expressed as a percentage of the controllevel. At the time of ingestion, the proportion of circulating CD34+cells is the same as the control. The peak increase in circulating CD34+cells was observed at about 10-30 minutes after consumption. At thistime point, the number of circulating CD34+ cells was increased 2-fold(greater that 200%) over the control value. By 1 hour after ingestion ofthe selectin-ligand containing extract of AFA, the circulating CD34+cells had returned to the baseline value. Therefore, an aqueous extractof AFA can enhance the release of endogenous stem cells (e.g. CD34+cells) from bone marrow and other anatomical sites into circulation.Consumption of the selectin-ligand containing extract of AFA mobilizesCD34+ stem cells.

Example 4 An Aqueous Extract of AFA Contains a Selectin Ligand

The experiments described below document that AFA contains awater-soluble compound that specifically reduces TQ1 immunostaining ofL-selectin on human lymphocytes, monocytes, and neutrophils.

Peripheral Blood Mononuclear Cells (PBMC) were isolated by layeringperipheral venous blood onto Ficoll-Hypaque (Amersham), and centrifugedfor 25 minutes at 400 g. The PBMC-rich interface was harvested, and thecells washed twice in RPMI. Polymorphonuclear Cells (PMN) were isolatedby mixing peripheral venous blood with dextran70 in 0.9% saline to afinal concentration of 1% dextran at room temperature. Sedimentation wasallowed for 1 hour. The leukocyte-rich supernatant was harvested and theleukocytes pelleted by centrifugation. The pellet was resuspended in 2ml of phosphate buffered saline which was then layered on top of 3 mlFicoll-Hypaque, and gradient centrifugation performed to separatemononuclear cells (lymphocytes and monocytes) from neutrophils. Thepellet containing neutrophils was resuspended in saline. Cells werewashed, resuspended in a nutrient-rich medium (RPMI 1640), and kept onice until use.

Fresh and formalin-fixed peripheral blood leukocytes were distributedinto wells in a V-bottom 96-well microtiter plate at the approximateconcentration of 10⁵ cells per well. A freshly prepared water-basedextract of the blue-green algae AFA was prepared in physiological salineand serial dilutions performed. Cells were resuspended in either PBS,PBS-AFA-W, PBS-AFA-W-azide, or PBS-PC at various dilutions. Cells wereincubated at room temperature and in the dark for 20 minutes. Theunfixed fraction was not in contact with sodium azide during treatmentwith AFA extract, but was resuspended in sodium azide-containing bufferfor subsequent immunostaining. This was to allow for free cytoskeletalmovements and shedding of L-selectin. The fraction that was kept in0.02% sodium azide was in contact with sodium azide during the wholeprocedure, both treatment with AFA extract and subsequentimmunostaining. Sodium azide blocks cytoskeletal movement and reduces orblocks L-selectin shedding. Therefore, any reduction in staining forL-selectin with a monoclonal antibody is due to direct competition witha compound in AFA Extract.

After incubation with or without Extract A (AFA-W) buffer was added, andcells centrifuged. Supernatant was discarded, and cells resuspended in avolume of 50 μl phosphate-buffered saline containing 1% fetal calf serumand 0.05% azide. Optimal amounts of monoclonal antibodies, as determinedby previous titrations, were added. Plates were incubated at roomtemperature for 10 minutes, buffer was added, and plates centrifuged.Supernatants were discarded, cells resuspended in 50 μl buffer, andfixed in 1% formalin. Samples were kept cold and dark until acquisitionby flow cytometry. Acquisition was performed within 24 hours offixation. The CD62L monoclonal antibody TQ1 (specific for theligand-binding area of the L-selectin molecule) linked to phycoerythrin(PE), was purchased from Coulter (Hialeah Fla.).

The incubation of PBMC and PMN with the water extract from AFA (AFA-W)resulted in reduction of immunostaining with the TQ1 anti-humanL-selectin monoclonal antibody, which is known to be specific for theligand-binding area of L-selectin (Spertini et al., J Immunol.147(3):942-9, 1991). The AFA-W mediated reduction of TQ1 staining wasstrongest on lymphocytes and PMN, but was also observed on monocytes(FIG. 2A). On lymphocytes and PMN, an approximate 40-70 fold reductionin TQ1 staining was seen when cells were pre-incubated with AFA-W, incontrast to a 15-fold reduction for monocytes.

The expression of CD11b was slightly up-regulated, while no significantchanges were observed for other adhesion markers (CD11a, CD18, CD29,CD49d, CD49e, and CD44). Formalin-fixed peripheral blood lymphocyteswere incubated in the absence or presence of serial dilutions of AFA-W.Staining of lymphocytes with the TQ1 antibody showed a dose-dependentreduction in TQ1 binding to L-selectin with increasing concentrations ofExtract A. As the effect was seen also on the formalin-fixedlymphocytes, the reduced staining could not be due to shedding ofL-selectin. (FIG. 2).

Example 5 AFA Selectin Ligand Blocks the Expression of ChemokineReceptors Triggered by Fucoidan in the KG-1a CD34^(bright) Cell Line

The primitive cell line KG-1a is brightly positive for CD34 and forL-selectin, as evaluated by staining with the TQ1 monoclonal antibody.KG-1a also contains intracellular reservoirs of the CXCR4 chemokinereceptor that are externalized upon L-selectin ligation. Incubation ofKG-1a with the Fucoidan, an L-selectin agonist, triggers the expressionof the chemokine receptor CXCR4. AFA Extract A blocked theFucoidan-mediated effect on CXCR4 expression (FIG. 3).

Example 6 Purification of the L-Selectin Ligand from AFA

A selectin ligand was isolated from AFA using magnetic beads covalentlybound to genetically engineered fusion protein in which theextracellular portion of human recombinant L-selectin or P-selectin iscoupled to the Fc portion of immunoglobulin. The beads are incubatedwith the water-soluble fraction of AFA and the selectin ligand isisolated (see FIG. 4A: L-selectin, FIG. 4B: P-selectin). The beads werecollected using a magnet and washed many times. The beads were thenexposed to an acid treatment or boiling or an alkaline treatment tobreak the bond between the ligand and the recombinant selectin. Theselectin ligand was also isolated using an affinity column.

When the selectin ligand is recovered under reducing conditions, it is adimer made of two subunits of approximately 54 kDa and 57 kDa (FIG. 4B).A composite molecule based on these subunits could have molecularweights of 108, 111, or 114 kDa approximately, and higher multiplicitiesthereof. Using size exclusion techniques, when the extract A fractionwas passed through a 100 kDa filter, the ligand was found in higherconcentrations in the fraction above 100 kDa. Therefore, the ligand canbe isolated as a dimer of at least 100 kDa.

Example 7 The Selectin Ligand Extracted from AFA is not a Found inExtract B

Extract B was produced in several steps, first by extracting compoundsinto ethanol, then back into a polar buffer (water, saline). The firststep was to produce a yellow/brown powder from dried AFA, initiallyduring 3 hours at 50° C. with an aqueous solution containing 20%ethanol. The supernatant was decanted and the solids were precipitatedby adding ethanol to a final 80% concentration. The precipitate wasdried using REFRACTANCE WINDOW™ drying technique. When this yellowpowder was put back into aqueous solution (water or saline), an orangeextract was produced. Solids were removed by centrifugation, and thesupernatant sterile filtered. This liquid is Extract B. This extract wasincubated with the coated magnetic beads described above. Extract B didnot contain a selectin ligand (FIG. 5).

Example 8 Selectin Ligand from Blue-Green Algae Modulates CXCR4Expression

Stem cells are maintained within the bone marrow environment at least inpart through the selectin adhesion molecules. When selectin is engagedby an appropriate ligand, it triggers the expression of the cytokinereceptor CXCR4. CXCR4 is a specific receptor for Stromal Derived Factor1 (SDF-1) and binding of SDF-1 to CXCR4 helps to maintain stem cellsbound to the bone morrow. Inhibition of selectin ligand binding reducesthe expression of CXCR4, which leads to a detachment of stem cells fromthe bone marrow and their release in the bloodstream.

To demonstrate the physiological effect of the selectin ligand from AFA,in one embodiment the selectin ligand was tested on CXCR4 expressiontriggered by fucoidan, a known L-selectin ligand that stimulates CXCR4expression. The expression of CXCR4 receptors following exposure tofucoidan was evaluated on lymphocytes using flow cytometry. Incubationwith the AFA selectin ligand significantly inhibited the expression ofCXCR4 on human lymphocytes (FIG. 6) and on the human CD34+ progenitorcell line KG-1a (FIG. 7), indicating that this is a mechanism by whichthe AFA selectin ligand can trigger stem cell mobilization.

Example 9 Stem Cells from Bone Marrow Populate Multiple Distant Tissues

A murine model can be used to evaluate the ability of stem cellsmobilized by consumption of blue-green algae to populate distant tissuesof the body. Male mice are selected as bone marrow donor animals, whileall recipient mice are females. Female recipients are sub-lethallyirradiated prior to injection of male bone marrow cells into their tailveins. Two groups of mice are evaluated. The first group of 20 animalsare sub-lethally irradiated, injected with bone marrow, and put onnormal feed. The second group of 20 animals is also sub-lethallyirradiated, receive male bone marrow, and are fed a diet of normal feedplus 0.5 to 15% w/v of the selectin-ligand containing fraction of AFA.

About 6×10⁶ nucleated cells of adult bone marrow is harvested from malemice aged 8-10 weeks and injected into the tail veins of sub-lethallyirradiated isogenic adult female recipients, also aged 8-10 weeks. Micefrom each group are sacrificed at each of the following time points:time 0, 1 week, 2 weeks, 3 weeks, 4 weeks, and 8 weeks. At time points 2and 8 weeks, 6 mice are sacrificed from each group. At all other timepoints, 2 mice are sacrificed from each group.

During the first two weeks after injection, 15 microliters of wholeblood is taken from the ear, tail, or paw, and immediately diluted in200 microliters of buffer (phosphate buffered saline, pH=7.2, 2% serum,0.02% azide) to dilute clotting factors and prevent coagulation. Theblood samples are assayed to monitor the repopulation of platelets, redblood cells, and leukocytes within the blood. A portion of the bloodsample is used for obtaining a cell count and for differentialevaluation of red blood cells versus white blood cells. The sample isassayed using a flow cytometer, and the proportion of neutrophils,lymphocytes, and monocytes will be evaluated using forward and sidescatter. The blood leukocytes will be examined for male origin usingflow cytometry.

At time of sacrifice, various cell and tissue types will be examined forHy antigen, which demonstrates that the cell or tissue originated in amale mouse. Brains are harvested and the entire brain is examined,including the olfactory bulb, hippocampus, cortical areas, andcerebellum. Bone marrow, heart muscle, hind leg muscle, liver, pancreas,sections of small intestine, and lung tissue are examined for presenceof cells with Y chromosome, either by detection of surface Hy antigen byimmunofluorescence, or by fluorescence in situ hybridization usingprobes for the Y chromosome. These data will document to what extent adiet containing blue-green algae promotes the homing, implantation, anddifferentiation process of the injected bone marrow stem cells.

Example 10 Stem Cells from Bone Marrow Populate Multiple Distant Tissues

A study similar to that described above is conducted using transgenicmale mice carrying the gene for green fluorescent protein (GFP) andisogenic female mice as recipients. The animals are treated, fed, andsacrificed as described above, and blood samples are also analyzed in asimilar manner.

Blood leukocytes are examined for the expression of GFP using flowcytometry and, at time of sacrifice, various cell and tissue types willbe examined for GFP antigen, which demonstrates the donor origin.Tissues and organs are harvested as described above and the presence ofcells carrying GFP is detected by flow cytometry or fluorescencemicroscopy.

Example 11 Increased Stem Cell Repopulation of Traumatized Tissue

A mouse model is used to evaluate homing and integration of bone marrowderived stem cells into traumatized tissue

All marrow donors are adult male mice (8-10 weeks of age), and allrecipient mice are adult females (8-10 weeks of age). Two groups of miceare evaluated. One group of sub-lethally irradiated recipients receive6×10⁶ nucleated donor cells via injection in the tail vein and allowed 2weeks of recovery. The animals are then lightly traumatized by thinneedle insertion into hind leg muscle, heart, and brain. All animalsreceive normal feed throughout the study. In the second group, femalemice are treated identically as the first group, but are fed a diet thatincludes 0.5 to 15% w/v of the selectin-ligand containing fraction ofAFA.

Two mice are sacrificed prior to trauma to evaluate baseline levels ofmale-derived cells. Subsequently, mice are sacrificed at the followingtime points: 1 week, 2 weeks, 3 weeks, and 4 weeks. Two mice aresacrificed for each time point, except for the 2 week time point, where6 mice are sacrificed from each group. Hind leg muscle, heart, and braintissue is isolated from the sacrificed animals. Sections are cut throughthe traumatized areas, and stained for male-derived cells using eithercell surface marker analysis for the expression of the Hy antigen or byfluorescence in situ hybridization using probes for the Y chromosome.Alternatively, a GFP-expressing transgenic donor mouse will be used(similar to Example #4).

Data obtained demonstrate the effect of consuming the selectin-ligandcontaining fraction of AFA on the speed of stem cell recruitmentfollowing trauma.

Example 12 Case Report for Tissue Repair

A subject was a body builder who had a car accident three years ago. Acar hit her car in the door on the driver's side and several muscleswere torn in her hip and thigh. She underwent a series of surgeries tore-attach the severed muscles. In spite of the successful surgeries, themuscle damage was so severe that she remained with a constant pain andcould not resume her weight lifting training, as even a mild trainingsession would be followed by swelling and pain, which would preventwalking for several days.

She tried many anti-inflammatory drugs, but after 18 months she stillcould not train. She began consuming the blue green algae fractioncontaining a selectin ligand. Two weeks later, she reported being ableto return to the gym, and after two months of consumption, she hadresumed normal training, indicating extensive repair of muscle tissue.

Example 13 Case Report for Tissue Repair

A 55 year old subject went for a sixth hip replacement—fourth on theleft side. Generally, there was a very poor prognosis and enormousdifficulties involved.

The orthopedic surgeon rebuilt the pelvis and acetabeum. However, priorto the surgery the subject was informed by the medical staff that therewas no way for the body to produce new bone necessary for the long termsuccess of the procedure. It was presented that if the subject was toget bone growth it likely would be less than required for healing.

The subject was provided with the blue-green algae fraction containingL-selectin shortly after the surgery. The new, strong bone growthappeared quickly and recovery was rapid. The subject reported that theyno longer needed crutches and was able to be on full weight bearingstatus in 6 weeks—compared to 6 months with the subject's previoussurgery. The subject reported that the accelerated healing was confirmedin every check-up. The subject also reported that the bone surroundingtheir right hip that had a revision done in early 80's was found verystrong. This was considered exceptional.

Example 14 Case Report

A young girl was diagnosed at the age of three with infantile musculardystrophy. She was unable to walk. She was very frail, and frequentlyexperienced pneumonia, which each time resulted in confinement to bedfor 8-10 days. She was on conventional therapy for muscular dystrophyfor six months, but this resulted in no change. She started consumingSpirulina, which to some extent improved her immune function as sheexperienced less frequent and less severe pneumonias. She then startedconsuming the blue green algae fraction containing a selectin ligand(Extract A). After two weeks she started taking her first steps. Afterthree months she was walking. She had no more pneumonia.

The disease is an inherited disease, and several family members withsame disease—but further degenerated—also started consuming the algaefraction (Extract A). These individuals reported that they experiencedbenefits of consuming this fraction.

Example 15 Human Studies

A triple-blinded, randomized, placebo-controlled study on human subjectswas conducted on the effect of various AFA extracts on the numbers ofcirculating stem cells. The following methods were used in thesestudies:

Consumables: Four consumables were tested. Two were liquid, and two wereencapsulated. Neither the volunteers, nor the person administering thesubstance, nor the lab staff performing data analysis knew whichsubstance was being administered at a given study day.

-   -   1. LSL: Extract A, an AFA fraction enriched in the L-selectin        ligand. One gram of the fraction concentrated in L-selectin        ligand (LSL) was mixed in 40 ml of water and served to study        subjects in a paper cup.    -   2. Migratose (MGT): The fraction known to contain the bioactive        compound responsible for the migration of immune and stem cells        was obtained by extracting liquid AFA with 10% ethanol at 50° C.        for one hour. The solution was centrifuged and the supernatant        was dried using RW. This product has been internally named        Migratose (MGT). Migratose (150 mg) was blended with 250 mg        placebo and administered in a vegetable capsule.    -   3. StemEnhance (SE): StemEnhance is a blend of LSL and        Migratose. One gram of StemEnhance was mixed in 40 ml of water        and served to study subjects in a paper cup.    -   4. Placebo: The placebo consisted of 400 mg green-dyed, finely        ground potato flakes encapsulated in vegetable capsules. The        appearance was identical to that of capsules containing        Migratose.

Subjects: A total of 19 people were interviewed from regularblood-donation healthy volunteers. The following exclusion criteria wereused:

Under 20 or over 65 years of age

Pregnancy

Severe asthma and allergies requiring daily medication

Any known chronic illness or previous/current venereal disease

Frequent recreational drug use

Impaired digestive function (including previous major gastrointestinalsurgery).

Of the people interviewed, 14 met the study criteria and were willing toparticipate. Among the 14, three were subsequently excluded part waythrough the study due to non-compliance. Among the remaining 11volunteers, six went through four study days each, such that data wasobtained for all four consumables on the same person. The remaining fivevolunteers were able to participate in three study days each.

Subjects were scheduled for arrival on the same weekday on foursuccessive weeks during a two month period. Subjects were scheduled onthe same weekday for greater consistency in the data. They wereinstructed to have a good night's sleep before each study day, and toeat the same type of bland breakfast on each study day.

Upon arrival, the volunteers were seated in quiet areas away from eachother, to discourage chatting and produce a quiet environment (therewere no disturbances such as phones, door bells, talking among labstaff). The volunteers were instructed to remain quiescent, comfortablysitting in a chair, for one hour. Movement was restricted to slowwalking to the bathroom, if needed. After one hour, the baseline bloodsample was drawn. Immediately after drawing the baseline sample, aconsumable was provided. The volunteers were instructed to remainquiescent for the whole duration of the experiment. Blood samples werelater drawn 30, 60 and 120 minutes after ingestion of the consumable.

Every day, upon arrival to the laboratory, volunteers filled aquestionnaire giving a daily assessment of their general conditions.This questionnaire was intended to identify any instance for which datapoints might have to be eliminated due to extraordinary circumstances.The following criteria were used for eliminating data points:

Lack of sleep

Stimulants within 2 hours of arrival

Stress.

Assessment of circulating stem cells: At each time point, 5 ml blood wasdrawn into heparin, and 2 ml blood was drawn into EDTA. The blood vialswere placed on a rocking plate until use. The blood drawn into EDTA wasused for obtaining a complete blood count (CBC) using a Coulter counter(Micro Diff II, Beckman Coulter). All CBCs were performed within an hourof drawing the sample. All CBCs were performed in triplicate.

The heparinized blood was used for purification of the peripheral bloodmononuclear cell fraction by gradient centrifugation, and processed forimmunostaining and flow cytometry. The stem cell markers CD34-FITC(clone 8G12) and CD133-PE were used for two-color immunofluorescence.Staining of all samples with CD34-FITC/CD133-PEW was performed intriplicate. Appropriate isotype controls were used in parallel samples.Positive controls for each donor included CD45 and CD14. Stained cellswere fixed in 1% formalin and acquired by flow cytometry immediately.Files of 200,000 events were collected on each sample.

Since the cells used for immunostaining did not include the granulocytepopulation, the acquisition of 200,000 events included more stem cellsthan if whole blood had been used. The use of the peripheral bloodmononuclear cell fraction thus allows collection of data with highernumbers of stem cells, giving a better statistical weight to observeddifferences in stem cell numbers.

Staining for CD14 was performed in parallel samples, as not to interferewith the analysis of CD34 and CD133. Flow cytometric analysis wasperformed using the CellQuest Pro software (Becton Dickinson).

The following results were obtained:

Consumption of SE and LSL led to an increase in the number ofcirculating CD34+ cells (see FIG. 9), while MGT led to a decrease in thenumber of circulating CD34+ cells. After consumption of placebo smallchanges that were not statistically significant were. With both SE andLSL a number of volunteers showed a tendency for an initial transientdecrease in the number of CD34+ cells; this observation was greater forLSL though did not reach significance. At sixty minutes afterconsumption, SE (p<0.003) and LSL (p<0.02 triggered a significantincrease in the number of CD34+ cells. However, MGT triggered asignificant decrease (p<0.03).

In a subsequent part of the data analysis, each volunteer's responses toAFA extracts were normalized to the same person's response to placebo.This was done by subtracting the percentage change obtained with theplacebo from the percentage change obtained with the extract. This wasdone for all three consumables. This procedure did not increase themagnitude or significance of the responses; the pattern obtained wassimilar to FIG. 9.

Another part of the data analysis focused on the maximum percent changefor each consumable compared to placebo. The rationale for this analysisis that the absorption of bioactive compounds, delivery to targetorgans, and time to generate a quantifiable physiological response maybe different depending on each volunteer's overall physiology. Thisanalysis method minimizes differences in individual response times andallows a comparison of the extent of change, irrespective of whether themaximum change was observed at 30 or 60 minutes. Based on this method a24±5% increase in the number of circulating stem cells with SE and a24±2% decrease with MGT was found. A median response of 27% and 77%,respectively, for SE and MGT was found.

The timeframe to reach maximal response appears to be of no more than afew weeks. To avoid a potential confounding factor in the data, most ofthe studies were performed on samples from subjects who regularlyconsumed AFA. In the present study, only one subject was not a regularconsumer of AFA. This one subject showed no noticeable increase in CD34+cells mobilization. It should be noted that this volunteer was removedfrom the analysis. As it was only a single subject who did not regularlyconsume AFA, the samples obtained from the subject could not be used fora relevant statistical analysis. In addition, one complication in thistype of protocol is the fact that individuals do not all mobilizeaccording to a similar time frame, and thus there may be anunder-estimation of the actual peak of mobilization. The response toplacebo showed variations, though such fluctuations did not reachstatistical significance. Nevertheless, these fluctuations appear to bereal and suggest that a better understanding of the daily cycling ofcirculating CD34+ could be of use in designing future studies.

This study confirmed that SE and LSL, both of which include a driedaqueous extract enriched for a selectin ligand, are effective atmobilizing bone marrow stem cells by increasing the number ofcirculating CD34+ cells. The data collected in this study show that SEincreases the number of circulating stem cells by up to 35%.

It will be apparent that the precise details of the methods orcompositions described may be varied or modified without departing fromthe spirit of the described invention. We claim all such modificationsand variations that fall within the scope and spirit of the claimsbelow.

1. An aqueous extract of Aphanizomenon flos aquae, wherein the extractis enriched for an L-selectin ligand.
 2. The aqueous extract of claim 1,wherein the aqueous extract is produced by suspending driedAphanizomenon flos aquae in water or a salt solution and removing solidmatter.
 3. A solid composition comprising a dried form of the aqueousextract of claim
 1. 4. A composition comprising a therapeuticallyeffective amount of the solid composition of claim 1 in apharmacologically acceptable carrier.
 5. The composition of claim 4,further comprising a therapeutically effective amount of a second solidcomposition, wherein the second solid composition is a dried form of asecond extract of Aphanizomenon flos aquae, and wherein the secondextract is an ethanol extract of Aphanizomenon flos aquae.
 6. Thecomposition of claim 5, wherein the ethanol extract is produced bysuspending dried Aphanizomenon flos aquae in about 10 to about 20percent ethanol at about 50° C. to about 60° C.
 7. The composition ofclaim 6, comprising 1 gram to about 2 grams of a dried aqueous extractof Aphanizomenon flos aquae, wherein the extract is enriched for anL-selectin ligand, and about 100 mg to about 500 mg of a dried ethanolextract of Aphanizomenon flos aquae.
 8. The composition of claim 7,comprising about 1 gram of a dried aqueous extract of Aphanizomenon flosaquae, wherein the extract is enriched for an L-selectin ligand, andabout 150 mg of a dried ethanol extract of Aphanizomenon flos aqua. 9.The composition of claim 6, produced by the process of contacting afirst amount of Aphanizomenon flos aquae in 0.1 molar phosphate bufferedsaline or water for about half an hour to about 12 hours to produce anaqueous extract; removing solid material from the aqueous extract;drying the aqueous extract to produce a solid composition comprising aL-selectin ligand; incubating a second amount of Aphanizomenon flosaquae in 10% ethanol at about 50° C. for about one hour to produce anethanol extract; removing solid material from the ethanol extract;drying the solid material from the ethanol extract to produce a solidform of the ethanol extract; and mixing a therapeutically effectiveamount of the solid composition comprising the L-selectin ligand and atherapeutically effective amount of the solid form of the ethanolextract.
 10. A purified selectin ligand isolated from a blue-green algaecomprising a protein or a glycoprotein of a molecular weight of about 55kDa under reducing conditions.
 11. The purified selectin ligand of claim10, wherein the selectin ligand has a molecular weight of about 54 kDaor about 57 kDa under reducing conditions.
 12. The purified selectinligand of claim 10, wherein the blue-green algae is Aphanizomenon flosaquae.
 13. The purified selectin ligand of claim 10, wherein theblue-green algae is a species of Spirulina.
 14. The purified selectinligand of claim 10, wherein the selectin ligand has a molecular weightof about 54 kDa, about 57 kDa, about 162 kDa, about 171 kDa, about 233kDa or about 111 kDa under non-reducing conditions.
 15. A pharmaceuticalcomposition comprising a therapeutically effective amount of thepurified selectin ligand of claim 10 in pharmaceutically acceptablecarrier.
 16. A method of mobilizing hematopoietic stem cells in asubject, comprising administering to the subject a therapeuticallyeffective amount of the purified selectin ligand of claim 10, therebymobilizing hematopoietic stem cells in the subject.
 17. The method ofclaim 16, wherein the hematopoietic stem cells express CD34 (CD34+),CD133 (CD133+), or both.
 18. The method of claim 16, wherein the subjectis human.
 19. The method of claim 16, further comprising measuring thenumber of CD34+ stem cells in the subject.
 20. The method of claim 16,wherein the subject is healthy.
 21. The method of claim 16, wherein thesubject is immunosuppressed or has a chronic illness, traumatic injury,or degenerative disease.
 22. The method of claim 16, wherein the subjecthas a disorder of the digestive system, nervous system, lymph system,cardiovascular system, or endocrine system.
 23. The method of claim 22,wherein the subject has osteoporosis, Alzheimer's disease, cardiacinfarction, Parkinson's disease, traumatic brain injury, multiplesclerosis or cirrhosis of the liver.
 24. The method of claim 16, wherestem cell homing is increased about 100% to about 500% as compared to acontrol.
 25. A method of mobilizing hematopoietic stem cells in asubject, comprising administering to the subject a therapeuticallyeffective amount of the composition of claim 1, thereby mobilizinghematopoietic stem cells in the subject.
 26. The method of claim 25,wherein the hematopoietic stem cells express CD34 (CD34+), CD133(CD133+), or both.
 27. The method of claim 25, wherein the subject ishuman.
 28. The method of claim 25, further comprising measuring thenumber of CD34+ stem cells in the subject.
 29. The method of claim 25,wherein the subject is healthy.
 30. The method of claim 25, wherein thesubject is immunosuppressed or has a chronic illness, traumatic injury,or degenerative disease.
 31. The method of claim 25, wherein the subjecthas a disorder of the digestive system, nervous system, lymph system,cardiovascular system, or endocrine system.
 32. The method of claim 31,wherein the subject has osteoporosis, Alzheimer's disease, cardiacinfarction, Parkinson's disease, traumatic brain injury, multiplesclerosis or cirrhosis of the liver.
 33. The method of claim 25, wherestem cell homing is increased about 100% to about 500% as compared to acontrol.
 34. A method of isolating a selectin ligand, comprisingextracting blue-green algae cells in an aqueous solution; separatingparticulate matter and isolating the resultant supernatant; contactingthe supernatant with a selectin bound to a solid substrate; andreleasing a ligand specifically bound to the selectin, thereby isolatingthe selectin ligand.
 35. The method of claim 34, wherein releasing theligand comprises treatment with acid, alkali, heat, or a combinationthereof.
 36. The method of claim 34, wherein the selectin comprises anextracellular domain of human L-selectin fused to an immunoglobulin Fcdomain or an extracellular domain of human P-selectin fused to animmunoglobulin Fc domain.
 37. The method of claim 34, wherein the solidsupport comprises magnetic beads.
 38. The method of claim 34, whereinthe blue-green algae is Aphanizomenon flos aquae.
 39. The method ofclaim 34, wherein the blue-green algae is Spirulina.
 40. A selectinligand, isolated by the method of claim
 34. 41. The selectin ligand ofclaim 34, wherein the blue-green algae cells are Aphanizomenon flosaquae.
 42. The selectin ligand of claim 34, wherein the blue-green algaecells are Spirulina.
 43. The purified selectin ligand of claim 10,wherein the ligand binds L-selectin, P-selectin, E-selection or anycombination thereof.
 44. The method of claim 16, wherein the selectincomprises L-selectin, P-selectin, E-selection, or any combinationthereof.